Idiopathic hypogonadotropic hypogonadism (IHH) is traditionally established by 1) the absence of spontaneous pubertal development by age 18 yr and 2) low sex steroids with inappropriately low gonadotropins in the absence of any functional or anatomic cause. To identify a novel disease locus for IHH, a genome wide scan was performed on a large, consanguineous Saudi family with 6 affected individuals. Linkage over a 1.06 Mb interval on chromosome 19p13.3 was established with a maximal two point LOD score of 5.17. Because numerous genes and hypothetical proteins are mapped to this region, further studies will be necessary to determine the precise genetic defect in this family.